Porcelain veneer crown and process of making same



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F. W. TEETER.

FILED JULY 29,1921.

.ant disadvantages of the latter.

Another object of my invention is to pro Patented Fish. i923.

FRANK W. TEETER, OF LA GRANGE, ILLXNOIS.

PORCELAIN VENEER CROWN AND PROCESS OF MAKING SAME.

Application filed July 29, 1921. Serial No. 483,303.

T 0 all whom it may concern Be it known that l, FRANK V. TEETER, acitizen of the United States, residing at La Grange, in the county ofCook and State of ing same.

In the art of dentistry, it has long been recognized that-many peoplefor aesthetic reasons, obj ct the ordinary full gold crown. To ,veiroinethis, porcelain jacket crowns have been used to a limited extent buttheporcelain jacket crowns are objectionable for the reason that theyrequire cutting away or trimming of the exposed part of the-teeth to agreater extent than with a gold crown and furthermore, the porcelainjacket crowns are comparatively weak and readily break. An additionalobjection in connection with the use of porcelain jacket crowns is that,on account of the deep cutting or trimming of the tooth required, it isgenerally necessary to employjan anesthetic.

One object of my invention is to provide a crown for teeth. which willossess the advantages of the ordinary gol crown as regardsstrength,sanitation and light; triinming of the tooth and which at thesame time will be free from the objectionable appearance of a full goldcrown and be as pleasing, from an aesthetic standpoint as a porcelainjacket crown without vide a novel, simple and eflicient process forprodueinga tooth crown of the character indicated in the precedingparagraph.

Other objects of the invention will more clearly appear from thedescription and claims hereinafter following:

In the drawing forming a part of this specification, Figure 1 1s aperspective view, on an enlarged scale, of a porcelain yeneer crownembodying my invention. Fig. 2 represents a vertical sectional view ofan anterior tooth showing my improved crown applied thereto.

Fig. 3 is a diagrammatic view of thepiain blank of gold-plate emtheattend-- ployed in the making of the shell of the crown. Fig. 4 is aperspective view repre senting the second step in the process of makingthe crown. Figs. 5, 6 and T are per-- spcctivc views representing thethird, fourth and fifth steps of the improved process of making thecrown. Fig. 8 is a vertical sectional view of the shell of the improvedcrown prior to the application of the porcelain veneer thereto. Fig. 9is a view similar to Fig. 8 showing the porcelain veneer in place and.Fig. 10 is a transverse sectional view of the complete crown takennearthe base thereof.

Broadly stated, the complete crown enibodies agold shell or crown properindicated broadly hy the reference A which is made, in accordance withthe process hereinafter described, to fit the previously prepared,exposed part of the tooth, said crown proper or shell completelyenveloping the prepared tooth. On the labial side of the crown isapplied a porcelain veneer or inset designated broadly by the referenceB,

parts oi the shell or crown proper being suitably burnished over theedges of the porcelain veneer, the veneer being additionally cemented tothe adjacent backing wall of the crown proper or shell A. It will benoted that, in the finished article, a reinforced tip or biting edge(made as hereinafter described) is formed as indicated at l1 and that"the only portions of the gold which will ordinarily be vis ble from theouter or labial side of the teeth will be relatively narrow edgeportions of the gold which immediately surround the porcelain veneerso'that the crown may be made to simulate the appearance of t-heenamelof the .original tooth and the contour of the porcelain made tocorrespond with the surface of the enamel originally on the labial sideof the tooth.-

In carrying out my invention, the following procedure is employed. Inthose'cases where the tooth is set back lingually or inwardly ofthe lineof arch, practically no dressing or preparation of the labial side ofthe tooth} is required since the porcelain veneer may. he made to servein restoring the normal arch line. In the cases where the tooth to beground is in the proper arch line. the same is separated at thenterproximal nary gold crown.

-in the usual manner employed with the ordi- 1 1c i cated at 12 in Fig.2;

partially removed. but ordinarily a thin layer of said enamel may beleft as indi- The lingual side of the tooth will ordinarily require noprepa ration since the lingual side ot the crown will be made to titthereover and. being ofthin metal.preferably ito-gauge. will not- .thegum line is then taken. which will govern the length of the blanksubsequently used. Next. a plaster impression of the tooth as preparedis taken. to he used in the making of the crown. Finally. a wax bite orimpression is obtained to enable the maker of the crown to properlyfinish the crown with respect to the biting edge and alincmentwith thetooth of the opposed jaw.

In making the crown. a blank t, of rectangular form and-0t the properlength'and width is taken. as shown in Fig. 3. the blank ordinarilybeing of 30 gauge ll & S gold sheet metal. The blank is then bent andthe edges l3-l3thereof brought together in a.

' butt jiiint as indicated at 13 in Fig. 4 and then soldered so as toproduce a substantially cylindrical product as indicated at t" in Fi al.i i

The cylinder C is thencut away on both sides from the top toward thebottom thereot ,so as to provide more or less U-shaped recesses Li and15 respectively. the size and contouis thereof approximating the labiallabial surface of the prepared tooth.

and lingual faces of the. prepared toot-h al-.

though there will be anexcess of the gold left in the form of upstandingprongs 16 and 17, for the purpose hereinafter described.

The article as last described is indicated at C in Fig.

The operator next cuts out a piece of the gold metal indicated at 18 in'Fig. 6 which corresponds. as nearly as possible. with thti Salt piece18 is then inserted within the shell C adjacent the recess 1-1 andpushed down into place leaving, however. outwardly extended relativelynarrow edge portions 1919 on the sides and rounded portion 21) at thebottom of. the shell manner, the piece 18 is pushed into place withinthe shell C so as to leave it slightly inwardly inset. The labial piece18 is then soldered to the. shell around all edges of contact so as toprovide a rigid and unitary the shell as C as shown in Fig.

Stated in another 6 is then treated so as to bend the prongs 16 and 17inwardly toward each other over the upper edge :ZLof the labial piece18, the prongs l6 and '17 being of such length that they will overlap.as shown at 16 andl'l'" in Fig. l. The overlapped portions thereof arethen soldered with a. lapped joint and the prongs in turn soldered tothe edge 21- ot' the labial piece 18. By providing a' lapped joint forthe prongs 16 and 1' 7, as described. it is evident that the tip orbiting edge of the crown is materially strengthencd and itiords agreater amount of metal to take care of the wear thereon.

The shell in theform as last described and as indicated at C" in Fig; 7;then has applied thereto a suitably cutpiece of the gold sheetmetalcorresponding to the lingual surface of the prepared toot-h. said piecebeing indicated at 22 in Fig. 8. The lingual piece :22 is titted withinthe remaining opening on the lingual side of the shell C and solderedsubstantially flush with the edges defining the recess 15 and the lappedprongs 16 and 17. As will be understood by those skilled in. the artthe.solder is applied from the insideof the she-ll and naturally there willbe an appreciable collection of the solder within the tip of the shellas indicated at 23 in 8 and 9, which will further strengthen the bitingedge of the crown.

recess that has been left on the shell onthe labial side thereof..Cement will be employed between the wall orpiece 18 of the shell andthe inner faceof the porcelain and thereafter the projecting edges l9and20 on the labial side of the shell will'be burnished over the edges ofthe poroelain veneer. producing the finished veneer crown as shown inFigs. 1. 2. t) and 10.

'llie crown proper or shell at this stage of its i In the drawing, Ihave illustrated a crown and process of making the same as employed fora central. lVhere 'the or'own. is to be applied to it posteriortootlathe process will be varied slightly so as to employa butt jointinstead of the lapped joint for the" prongs 16 and 17 and in addition acusp piece will be soldered on to the end of the shell. I

Among other advantages of my improved porcelain veneer crown, notheretofore men-. tioned. are the following. lVhei e the crown is to beused as a bridge abutment, the shell without the porcelain veneer may beapplied tothe prepared tooth and all attachments made thereto afterwhich the porcelain ve neer may be readily applied and secured in place,by

thereover. Furthermore, in the eyent the porcelain veneer becomesbroken, it may be readily replaced without removing the shell portion ofthe crown from the tooth which is of the utmost importance to the wearerof the crown since it does not interfere with the use of his tooth whilethe new part is being made.

I have herein shown and described what I now consider the preferredmanner of carry .i'ng out the invention.

All changes and modifications that come within the scope of the claimsappended hereto, are contemplated.

I claim 1. The herein described process of making a porcelain veneercrown for a tooth which consists in the following steps: taking a blankof gold sheet metal of rectangularform and of proper size; bending saidblank into substantially cylindrical form .nd soldering the meetingedges thereof. with a butt joint; cutting out portions of saidcylindrically-formed blank on the sides thereof corresponding to thelabial and lingual sides of the tooth; shell adjacent the labial recessthereof, a labial wall of gold metal; bending over the projecting prongsof' the cut shell and soldering said prongs over and to the adjacent endof said labial Wall; soldering to the shell thus formed within thelabial recess, alabial wall of gold sheet metal; preparing a porcelainveneer corresponding to the labial surface of the tooth; cementing saidveneer to said labial wall of the shell; and then burnishing the edgesofthe shell surrounding the veneer over the edges of the latter.

2. The herein described process of mak ing a porcelain veneer crown fora tooth which consists of the followlng steps: preparing a hollow sheetmetal shell to conform to and adapted to completely envelop theprotruding portion of a previously preburnishingthe edges of the shell'within the offset j substantially soldering to said out pared tooth,said shell having walls on the labial and lingual sides thereof, thewall on the labial side being inwardly offset; reinforcing the bitingedge of the shell; preparing a porcelain veneer corresponding to thelabial surfaceof the tooth; inserting said veneer on the labial side ofsaid shell provided by said inset labial. wall of the shell; 'the edgesof the shell surrounding said inset in said labial wall thereof over theedges of the porcelain veneer.

3. As an article of manufacture, a porcelain veneer crown for a toothcomprising: a hollow sheet metal shell conforming to and adapted toenvelop and fit over the exposed portionof a previously prepared tooth,said shell having an inset wall on the labial side thereof extendingfrom the base to the biting edge of the crown, the biting edge beingformed on the shell and constituting the union between said labial walland. the lingual wall of the shell of a porcelain veneer mounted on theouter surface of said inset labial wall of the shell and retained inplace by the edge portions of the shell surrounding said inset wall,sa-id edge portions being burnished over the edges of the porcelainveneer.

l. As an article of manufacture, a porcelain veneer crown for a toothcomprising: a hollow metallicshell conforming to and adapted to envelopa previously prepared tooth, said shell having a labial wall and alingual wall united at the biting surface of the crown, the labial wallof the shell being inwardly offset with respect to the surroundingedgeportions of the shell and a veneer rigidly aiiixed to said insetwall within said surrounding edge portions thereof.

In witness that I claim the foregoing l have hereunto subscribed my namethis 26th day of July 1921.

FRANK W. TEETER. Witnesses:

P. M. Mansion, ANN BAKER.

and then burnishing

